Means for igniting and controlling low-gravity-fuel burners



Oct. 7, 1930. D. M. PEARSON MEANS'FOR IGNITING AND CONTROLLING LOWGRAVITY FUEL BURNERS Filed April 3, 1929 INVENTOR.

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Patented Oct. 7, 1930 UNITED STA ES PATENT OFFICE DONALD PEARSON, OIOAKLAND, CALIFORNIA.

MEANS FOR IGNITING AND CONTROLLING LOW-GBAVITY-FUEL B'O'BNEBBApplication filed April 3,

My invention has for its object anelectrically controlled heating s stemwherein vaporized fuel, ordinarily di cult of vaporization and ignitionat room temperatures,

is employed.

By my invention such fuel is first heated and then in its vaporizedstate is readily ignited. I therefore provide a preheating means wherebythe passages into which the cold fuel is to be introduced and throughwhich it passes, are first brought to a temerature corresponding withthat at which uel will be properly preheated.

When such temperatureis reached, this preheating step is discontinuedand the full fuel flame being immediately established under theincreased preheating temperature condition, is thereafter maintainedcontinuously.

2 By reference to the accompanying drawing. my invention will be madeclear.

Fig. 1 is a diagram of the electrical circuit and operating elementsshowing one form of my invention as applied to fuel burners.

Fig. 2 is a mdification of Fig. 1 wherein a thermostat control issubstituted for the time delay switch.

Fig. 3 illustrates an alternate form of electrically heating the fuelsupply.

A conventional llquid fuel supply is indicated by the numeral 1 fromwhich oil is abstracted by a conventional electrically op: erated pump2, through the delivery pipe 3, to the chamber 4 within which the. oilis 'vaporized and from which it issues through the tip 5 into the burnerbase 6, and is there mixed with air drawn in through the inlet 7 andburns under the chamber 4.

At. 8 is a conventional source of electric energy controlled through theswitch ,9; one circuit leg from the switch is grounded and the other legshown at 10, energizes the movable contact 11 and initiates movement ofthe time delay switch 12. i

The movable contact 11 is actuated through the relay coil 13 to breakthe circuit between contacts 11 and 14 when energized after the timedelay switch 12 closes its contacts at 30.

When the contacts 11 and'14 are closed the 50 first action is thatthecircuit branch 15 is stantly a large gas flame to the burner 6.

1929. Serial No. 852,082..

very low, as under WLIlteI or freezing condi f 001 4 tions, to furnishin circuit with the branch 15, an electric heating element 18 whichheats the lower portion of the burner base and throat through which theair and gas is introduced, thus preventing condensation and 66facilitating the ready ignition of the fuel va or, when it isintroduced.

he time delay switch 12 starts flmctioning as soon as the switch 9 isclosed and the as flame now being fully turned on, the chem r 70' 4becomes heated and likewise the walls of the burner base 6. a

After a predetermined time interval, the time dela switch 12 closesitscontacts at 30 and the circuit leg 20 is energized, thus causcomes deadand the gas valve 16 now closes under the action of the spring 31.

Thereafter, during the full operationof the burner, the relay 13 holdscontacts 11 and 21 in engagement as long as the throw switch 1 at 9remains closed.

This closing of contacts 11 and 21 starts 35 the pump 2, which nowsupplies fuel to the heated chamber 4:, where it is vaporized, and itthen issues from the tip 5 as a continually burning fuel spray.

When it is desired to shut off the 'burner flame, the switch 9 isopened, de-energizing. the relay 13 when contacts 11 and 21 are brokenand the pump 2 stops and contacts 11 temperature increase closescontacts 60 and f ergizes the relay 13 causing the contacts 11 and 21 toclose, the gas valve 16 closes off the supply of gas and the pump startsinto' operation.

It is of course desirable to maintain a pilot light or otherconventional ignition means as an electric spark, not shown but wellknown, to ignite the gas when the gas valve 16 is first turned on andwhile I have shown an electrically controlled gas valve and gas supplyto preheat the chamber 4, an electric 'heatin means for the chamber 4may be substitute therefor in circuit with the contacts 11, 14,functioning the same way as does the gas flame to initially heat thechamber and I wish to be understood as claiming all such.

Such an electric heating means is illustrated diagrammatically in Fig.3, wherein the chamber 4 is provided with a heating coil 70, connectedthrough conductor 15 with the contact 14 and thence to ground andwherein the coil 18, if employed, is likewise connected and parallelwith the coil 7.

I claim:

1. Means for igniting and controlling the fuel supply to a doubleburner, which consists of a gas supply and a gas valve and connectionstherefrom to and including a burner tip, a vaporizing chamber and meansadapted to introduce liquid fuel into said chambena vapor connectionfrom said chamber to said burner tip, an electric circuit and devicesadapted to open said gas valve to preheat said chamber, automatic meansoperating to close said valve when said chamber has arrived at apredetermined temperature and to actuate said means to introduce liquidfuel into said chamber where it is vaporized and passes through saidconnection and sa d tip, and a heating element in front of said tip andin circuit with said valve whereby the passage walls through which thegas passes on leaving the tip are simultaneously preheated.

22. Means for igniting and controlling the fuel supply to a doubleburner, which consists of a gas supply and a gas valve and connectionstherefrom to and including a burner tip, a vaporizing chamber and meansadapted to introduce liquid fuel into said chamber, a vapor connectionfrom said chamher to said burner tip, an electric circuit and devicesadapted to open said gas valve to preheat said chamber, a thermostatwithin said vaporizing chamber, contacts actuated by said thermostat anda relay excited by the closing of said contacts whereby the circuit anddevices operate to close said valve when said chamber has arrived at apredetermined temperature and to actuate said means to introduce liquidfuel into said chamber where it is vaporized and passes through saidconnection and said tip.

3. Means for igniting and controlling the fuel supply to a doubleburner, which consists of a gas supply and a gas valve and connectionstherefrom to and including a burner tip, a vaporizing chamber and meansadapted to introduce li uid fuel into said chamber, a vapor connectionfrom said chamber to said burner tip, an electric circuit and devicesadapted to open said gas valve to preheat said chamber, a thermostatwithin said vaporizing chamber, contacts actuated by said thermostat anda relay excited by the closing of said contacts whereby the circuit anddevices operate to close said valve when said chamber has arrived at apredetermined temperature andjco actuate said means to introduce. liquidfuel into said chamber where it is vaporized and passes through saidconnection and said tip, and an electric heating element in the path ofsaid gas issuing from said tip in said circuit and adapted to beenergized during said gas fiow.

DONALD M. PEARSON.

